A couple of recipes from the web:
Take about 3 pounds of Rowan berries and two pounds of juicy apples. Peel and core the apples, slice them and place them to simmer in 2 pints of water for 10 minutes, while you are washing and sorting the berries. Add the berries and simmer to a pulp. Use a potato masher to help this process if you like. Let the mixture cool a bit and then strain it through a jelly bag, leaving it to drip overnight.
Warm about 2 pounds of sugar and stir in the liquid mixture and heat to a simmer. I must admit to adding some pectin at this point as I have a problem with runny jams. You can do this and leave the apples out for a clear jelly. Add a knob of butter and stir to a rolling boil for a few minutes and put it into sterilised jars and seal. It is a most unusual taste but the thing that delights me most about this jelly is the fantastic colour. http://www.simonthescribe.co.uk/ROWAN%20JELLY.html
Makes: 1.4 - 1.8kg (3 - 4lb)
900g (2lb) Rowan Berry
900g (2lb) Crab Apples
1.8lt (3 pints) Water
Pick over the rowan berries, removing any stalks, wash if necessary, drying well.
Wash the whole crab apples, removing any bruised parts.
Place the fruit and just enough water to cover into a heavy bottomed saucepan.
Bring to the boil and simmer, covered for 20 - 25 minutes, until tender.
Strain through a jelly bag or muslin cloth, allow about 4 hours for this, do not squeeze as this will cause the jelly to become cloudy.
Measure the volume of the liquid, add 450g (1lb) of sugar for each pint (600ml) of liquid.
Place the sugar in an ovenproof bowl and put it in the centre of a pre-heated oven for 10 - 15 minutes.
Place the juice back into a heavy bottomed saucepan, add the sugar, stirring until fully dissolved.
Bring to the boil and cook rapidly for 10 - 15 minutes until the setting point is reached.
Skim the surface if necessary, allow to cool slightly then pot. http://thefoody.com/preserves/rowanjelly.html